Decay of P-32, although producing S-32, will only rarely result in the
replacement reaction. Of prime concern should be the radiolysis of the
labeled mixture. The betas will generate many thousands of ions,
radicals, and excited molecules within a millimeter of their
'production'. These, obviously, are very chemically reactive, and
frequently catalytic too.
Paul J. Karol
Nuclear Chemist
(but not Radiation Chemist...a radiation chemist will be able to provide
more detailed information)